1. Field of the Invention
The present invention generally relates to munitions employing propellant with temperature dependent performance characteristics and, more particularly, is concerned with a temperature compensating control system for adjusting primary propellant chamber volume in a round of ammunition.
2. Description of the Prior Art
Projectile munitions have varied performance dependent on environmental temperatures. Propellants of the munitions typically provide high velocity performance under high ambient temperatures. However, under cold conditions such munitions provide low velocity performance due to the slower burn rate of propellants.
For reasons of safety of firing crews and of avoiding excessive stress on firing mechanisms, most munitions are designed to be safe at high ambient temperatures. Such a design results in low performance munitions at medium or low temperature climatic conditions.
One approach to temperature compensating control of projectile munitions propellants for improving munitions performance at all environmental temperatures, i.e., temperature independent performance, is disclosed in the patent application cross-referenced above (but is not considered to be prior art to the present invention). In the cross-referenced application, temperature compensation is achieved by use of a separate variable stroke drive ram system for loading and adjusting the position of the projectile and thereby the volume of the propellant chamber.
Although this approach constitutes steps in the right direction, other approaches still need to be explored in searching for ways to ensure optimal performance of projectile munitions at all environmental temperatures. The referenced application would require a major redesign of an existing gun system. This invention utilizes a concept that can potentially be applied to a broader range of new and existing gun and ammunition systems.